The Belgian geologist and mining entrepreneur André Dumont (1847-1920) had been working on the idea of finding hard coal in the Belgian heath landscape De Kempen since 1877. After years of unsuccessful drilling attempts, he made a find in 1901 in the municipality of As: the drill bit struck coal for the first time at a depth of 541 metres. This was the starting point of mining in the Kempen coal basin which later took place in seven collieries.
A replica of the 31-metre-high drilling tower was erected near the railway station in As and is accessible as an observation tower with views over the Hoge Kempen National Park.
The As railway station that was built in 1878 is the oldest in Limburg. Thousands of coal miners arrived here in order to work in the mines of Limburg. Today the former coal station it is one of the entrances to the ‘Hoge Kempen’ National Park.